The battle for the best base layer has a new contender. The Alpacas of Montana Base Layer Quarter Zip uses a blend of alpaca wool and silk, so it’s extremely soft without any traditional wool-itch. Alpaca wool is warmer than other natural fibers, wicks moisture more efficiently, and is breathable. My favorite feature is that it’s naturally anti-microbial, so the bacteria that builds up when wearing the base layer doesn’t stick around and start stinking again once my body heats up. This has become my go to base layer in cold conditions and kept me comfortable on warm days on its own. $200.